Spring-belt stretcher



Dec. 18, 1928.

H. BENIT SPRING BELT STRETCHER Filed July 19. 1926 IIIII lllllllllll Patented Dec. 18,

UNITED STA HENRI BnNIT, or rams,

YESIPATENT OFFICE.

SPRING-BELT s'rnnrcnna.

Application filed July 19, 1926, Serial No. 123,533, and iii-France July 25, 1925.

V Dynamos employed for lighting railway carriages are generally suspended from brackets fixed either to the underframe or to the bogies of the carriages.

These dynamos are driven by belts and pulleys, the driving pulleys being fixed on. the axles I of the carriages. In order to stretch the belt in such a way as to transmit power to the dynamo, the latter can either be inclined through a certain angle with reference to the vertical plane passing through its axis of suspension, the weight of the dynamo being thus utilized to produce tension, or an adjustable or non-adjustable spring stretch 5 ing device can be employed which acts on the dynamo in such a way as to produce tension in the belt. A combination of the two methods can also be employed. I

The object of the present invention is an '20 adjustable spring belt stretcher, more par- 'ticularly applicable to railway carriage light ing dynamos. The characteristics of this stretching device are its simplicity and its flexibility. An embodiment of the invention is repre- I sented, by way of exampleonly, in the accompanying drawing wherein: I

Fig. 1 represents a dynamo, fitted with its stretching device, fixed to the undertrame of a carriage. Fig. 2 is a view of the stretching device on a larger scale. 2

Fig. 3 is a cross section along line a, b, c, of Fig. 2. p v

On all the figures the sameparts are designated by the same reference numbers: 1 represents the dynamo, 2 represents the dynamo pulley, 3 the driving pulley fixed on the axle,

4 the belt, 5 the carriage wheel, 6 the bracket 4 from which the dynamo is suspended, 7 the dynamo suspension lugs. 2

The object of the stretching device is to produce tension in the belt 1. This stretching device includes a ratchet wheel 8 looselyv mounted on the dynamo suspension pin 9, a

helical springlO whose ends are bent along a diameter in such a way that the end 1.1 points towards the centre of the coils and the end 12 in the opposite direction. The ratchet wheel 8 is prevented from n1oving by means of a hinged pawl 13 suspended from the suspension bracket 6 of the dynamo. The lever 16, mounted on the pin 9, is provided with a pawl which engages-with-the teeth of rotation against vA plate spring 17 holds place. As shown in 1 is inclined and the the ratchet wheel. the pawl or ratchet in the figure, the dynamo component of its weight serves to stretch the belt partially. In order to obtain full tension, it su'liices to turn the wheel 8 in the .direction of the arrowby means of the lever 16 and'the teeth 01. the ratchet wheel.

11 of thespring', which is held. inithe groove flat of the ratchet wheel, is thus drawn round with the latter, while the end 12, which bears on the boss 15 on the dynamo, increases the tension of the belt.

The spring jaws 18 fixed to the casing of the dynamo hold the lever 16 when not in use.

Having thus fully described the invention, what I claim as new and desire to protect by Letters Patent is:

1. A tension regulating device for driving belts comprising a support bracket, a pulley supporting member pivotally connected with thebracket,-a ratchet rotatably mounted on the pivot: including acylindrical body and a toothed wheel fixed on one end of, the body, a tension spring wound about the body having' one end secured thereto and the opposite end attached to the pulley supporting mem-' 'ber, means for securing against rotation in one direction, and a lever operatively' associated withthe pivot and ratchet wheel adapted to permit rotation of the ratchet wheel in opposite direction to increase the tension or the spring.

2. A tension regulating device for drivingbelts comprising a support bracket, a pivot pin mounted in the bracket, a. pulley support ing member pivotally connected with the pin,

a ratchet rotatably mounted on the saidpin The end the ratchet wheel including a cylindrical body and a toothed wheel fixed onone end of the body, a helical spring wound about the body having one end secured thereto and the opposite end attached to the pulley siijiiporting member so as to exert a tension on the drive belt of the pulley, means for securing the ratchet wheel against the tension of the spring, and a lever pivotally connected with the pivot pin operable to engage the ratchet wheel for rotation of the ratchet wheel to increase the tension of the spring on the pulley member.

In witness whereof I have hereunto set my hand. i

HENRI BENI 

